SpaceX reaches agreement with astronomers to limit Starlink interference

This week, National Science Foundation announced it has reached an agreement with SpaceX to limit the effects of Starlink satellites on astronomy. Astronomers have been

raising concerns about the effects that Starlink satellites could have on scientific study for several years now, as part of a wider consideration of the cultural and

environmental importance of dark and quiet skies. The International Astronomical Union has even set up a special center for addressing the issue of satellite megaconstellations

like Starlink on both optical and radio astronomy. There are two main concerns about the impact of Starlink on astronomy. Firstly, that satellites are reflective so they

reflect light from the sun, leading to bright streaks in optical astronomical observations of the night sky. This is a particular problem for Starlink compared to other types of

satellites as the Starlink satellites sit in very low Earth orbit, meaning they are more prominent in the sky, and there are thousands of them. SpaceX has been working with

astronomers to reduce this issue through methods like painting the satellites a darker color to make them less reflective, adding sunshades, and changing their orientation so they

reflect less sunlight. The second problem is with radio astronomy. Satellites are designed to operate at a particular radio frequency, however, they can give off radiation

outside that band in a phenomenon called frequency bleed. Radio astronomers already have to deal with a lot of background radio noise from Earth to pick out the faint signals from

the distant objects they are observing, and having many satellites in the sky makes that harder.